Mysql分页存储过程

CREATE TABLE `ttt` (
  `a` int(11) NOT NULL DEFAULT '0',
  `b` varchar(6) DEFAULT NULL,
  PRIMARY KEY (`a`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;



INSERT INTO `ttt` VALUES (1, '2');
INSERT INTO `ttt` VALUES (2, '4');
INSERT INTO `ttt` VALUES (3, '3');

CREATE DEFINER=`root`@`localhost` PROCEDURE `pr_pager`(

IN p_table_name VARCHAR(1024),/*表名*/
IN p_fields VARCHAR(1024),/*查询字段*/
IN p_page_size INT,/*每页记录数*/
IN p_page_now INT,/*当前页*/
IN p_order_string VARCHAR(128),/*排序条件(包含ORDER关键字,可为空)*/
IN p_where_string VARCHAR(1024),/*WHERE条件(包含WHERE关键字,可为空)*/
OUT p_out_rows INT/*输出记录总数*/

)
    COMMENT '分页存储过程'
BEGIN

/*定义变量*/
DECLARE m_begin_row INT DEFAULT 0;
DECLARE m_limit_string CHAR(64);

/*构造语句*/
SET m_begin_row = (p_page_now - 1) * p_page_size;
SET m_limit_string = CONCAT(' LIMIT ', m_begin_row, ', ', p_page_size);

SET @COUNT_STRING = CONCAT('SELECT COUNT(*) INTO @ROWS_TOTAL FROM ', p_table_name, ' ', p_where_string);
SET @MAIN_STRING = CONCAT('SELECT ', p_fields, ' FROM ', p_table_name, ' ', p_where_string, ' ', p_order_string, m_limit_string);

/*预处理*/
PREPARE count_stmt FROM @COUNT_STRING;
EXECUTE count_stmt;
DEALLOCATE PREPARE count_stmt;
SET p_out_rows = @ROWS_TOTAL;

PREPARE main_stmt FROM @MAIN_STRING;
EXECUTE main_stmt;
DEALLOCATE PREPARE main_stmt;

END


call pr_pager("ttt","a",3,1, "","",@result);